diff --git a/sys/net/gnrc/network_layer/ipv6/nib/_nib-slaac.c b/sys/net/gnrc/network_layer/ipv6/nib/_nib-slaac.c
index f34f88c5ced11409c68e9b56a07979ea9ba5e1e9..e32896d119e97bf59bb7b8727054b4f050965303 100644
--- a/sys/net/gnrc/network_layer/ipv6/nib/_nib-slaac.c
+++ b/sys/net/gnrc/network_layer/ipv6/nib/_nib-slaac.c
@@ -24,9 +24,9 @@
 #define ENABLE_DEBUG    (0)
 #include "debug.h"
 
+#if GNRC_IPV6_NIB_CONF_6LN || GNRC_IPV6_NIB_CONF_SLAAC
 static char addr_str[IPV6_ADDR_MAX_STR_LEN];
 
-#if GNRC_IPV6_NIB_CONF_6LN || GNRC_IPV6_NIB_CONF_SLAAC
 void _auto_configure_addr(gnrc_netif_t *netif, const ipv6_addr_t *pfx,
                           uint8_t pfx_len)
 {